Bastian Strayd and his family lived on the planet Starhaven as part of the Valerians community. After the death of their parents in a 10-year war, Bastian and his younger sister, Lyra, were forced to leave Starhaven. They were locked below deck of a clandestine starship in the dark for six weeks.
In 2015, Bastian and Lyra made it to Earth and eventually started working for a gang of art thieves. The gang had Bastian and Lyra use their species' inability to be seen in security cameras and photos to conduct heists on valuable art in various museums. With Lyra's help, Bastian stole a Rodin from the Modern Arts Cultural Museum of National City and an original Warhol from the Art Institute of Metropolis.
In March 2017, the gang imprisoned Bastian when they began to believe he wasn't pulling his weight. Lyra agreed to clear his debt and conned Winn Schott to helping her steal Starry Night from the National City Art Gallery.
However, Alex Danvers and James Olsen intervened and took the painting when Lyra attempted to frame Winn. Distressed, Lyra told Winn that the gang would kill Bastian if the painting wasn't sold to their buyer, Mandrax. With the D.E.O.'s help, they set up a sting operation with a fake painting. Mandrax and the gang members were arrested, freeing Bastian from their control.